Telephone system.



. E. KEiTH.

TELEPHONE SYSTEM.

APPLzcATmN mw oc1r.21i 1904. REHEWED MAY 24, w18.

11 'SHEETS-SHED 2* KEITH.

TELEPHONE SYSTEM, l /wPLlcATioi-s man o'r. 2z. :904. www ww 24, was.

H SHEETS-SHEET 4.

E.' KEHH. TELEPHONE SYSTEM. APPLICATION man 007.21. |904.

RENEWED MAY 24.1918- SHEETS-SHE? 9.

A. E. KEHH.

, TELEPHONE SYSTEM.

APPLICATION FILED OCT.21.1904. EENEWED MAY 24 PH A Y rammed 3fm. 7, 1919.

Il `SHEETSASHET 10A E. Kami, TELEPHONE SYSTEM.

APPLICATION FILED OCT` 2lz 1904. RENEWED MAY 24.1918.

www

@ook s. ce1-mn new zum Telephone Sys'ms? is a spa-13.1115@ 'l inval/1 l :us Compris@ m 1L: lime connecbion4 from su Y SWE mcenra sin feaureg and mb For example l5 looking it in en@ Na it @mitm tephone m having :m ejac 13039,@ aux lary n; than h@ sa j t miam and anni 11e imm W the nlm/uber between ik@ if stations s played trashing station can 'ne nel in an airtight or inelcsure locate ier in or on tog) o?? a. buildin-gin a. man-hole, on rop of a pole, in a police hex, or in other vsuitable location; and it is thus evidentthat iliarv trunliin stations the main trunliinff s 5 o station being situated in a suitable building, while the auxiliary trunling stations consistl merely of comparatively small air-tight or inclosures containing the necessary automatic switching devices andlocated in any convenient place or locality; and it elnvieus that these auxiliary trunliing stations can loe exposed to the weather or protected a building 'without in any way interfering with the ellieiency ci? the apparatus and system a Whole. All of tl'iese., and other "succs, both creed anfl specific, are within e contemplation oli my invention; and the character, and its ilicrent features and will l'iereinaiiter more fully appear, a though it may he slated at this juncture that the objct ol the invention, Generally stated, is te provide a telephone svstezn wl'ich will he cheaper anal more eeonm.y l install and maintain, particuias-ly Willi to the wiring' or line commotion he en L .ie different Watkins.

in the aoco ipany sur drawings, lilium-e l s grapaic or {litigi-a nnatc repre. f: tarii'jin Gi" the Jnetlioel of wiring or connecting up the .main auf? ai iliary trunliing stations 'with the .f-uhserliers stations o1" a telephone ern einliocying the lnrinciples of my i am an -ation illustrating in a more o less fiiigraniciaic manner the inethoil oit loca-.tA

j the 'ii'lsilary Linking stations En diient Ways and pla( Fig.A is a perspective view eiE a pole-lop form of auxiliary t'runlringg station;

Fig. shows a man-holo form of auxiliar;A trunling station; v

Figs. '(3, Y and illustrate round and square mnlslruclious of casing or inclosure for the. auxiliary trunling' station apparail-us, :nul show the method of heating they ino of such inclosure;

s. l l) :unl ll arf: respectively' the le 'Y .iuiul portions nl ig lc apparatus of l l auiilmry fruultiug siations,

pcciiveh a` plan und vantages of a s3. stein of the foregcing and showing three subscribers stations .which are connected with each of the two Figl illustrates tlie'called suhscribers `v apparatus.

There are many existing and Well understool lfincls of switchboard apparatus. There is the Well-known manual board in which the connections between subscribers lines are established manually by means of cord-circuits and plugswitches, and there are also, at the present time, several foi-ins of automatic apparatus which. are Well known to those skilled in the arte-that is to say, autoi'natic switching apparatus whereby connection between one subscribers line and another is accomplished automatically by the calling subscriber, without the aid of a switchboard operator. For this reason, it is evident that no detail or extensive description of such apparatus is necessary, al though seine well-known automatic apparatus is hereinafter described. It is within the contemplation of my invention 'to einploy either ina-,mal or automatic apparatus;

but in view of the -fact that better service Ato greater advantage to autoniatic'telephone service, 'will hereinafter more fully appear; but at the same time it will be readily unclerstooll that, previously stated, the apparatus employed at the main and auxiliary trunling stations, and 'at the .subscrihers stations, may he of any suitable, known or approved 'orin. In `View of these i'acs, lfhare not, therefore, in the drawings, attempted to ininutely or eXha-ustively illustrate the details and mechanical construction ol the different devices and apparatus, but have simply shown clearly the method of connecting the main trunking station with tlvy auxiliary trunliing stations, and of connecting the subscribers stations with the said auxiliary stations; and in so doing the automatic switchinpT devices at the said trunking stations have'been shown more or less diagrannnatically and only in such .manner as isieci-ssary to a full understandingr of my invention. indeed, the automatic switclilmarrl apparatus shown in Figs. 9, l() .unl ll, and. in Figs. 12, i3 and le, is of the aiaractcr, nia] l cnaraceer ou of egviezating d connectonsu'itchesll t vdevices of i and will Li this con lecticn, that n, shown and described -s on the stepl-by-step ich o* course, necessitates the subscribers stations 'of inaiie-vandiareair devices for eiectrieal impulses over the` line Ling the connections, carrying on telephonie and for this reason the res, sivitclnhoolrs, etc., for iiiustrated diagrammati- ,Wter of tact, my invention,

" iroved si gnaling systo use in connectie or ever, referring to nge, my invention conn 'o trunlringp; station A, and any or practicable number of ition ion bytrunk lines. ranking station may e building, and the ions S, C, D, E, F, d at various points om the said main ne illustration, the ion be located 'y or town` and the ations then located in is o say, an auxiliary be allotted to each. or to any en i a illustrated.; the n t', di, e, ,'J, g, ,i and z' rivate or individual line dotted auxiliary trunlring however, that the ons canlie built for ci subscribers; but l' fuernent involving; 200 or Y .Se than G, subscribers truniring' station gives uws, as such a number for sier to handle. it' 200 subto each auxiliary truukany suitable munter of trani?,

.lines can then be employed vbetween each auxiliary 'trunliing station and the main truiilginggo station; and with 1GO subscribers aliotted to each auxiliary trunling station, l. find that 2U t inlrlines between' each aun- "ary trunlina' station and the niain trunk- 'll Ll ng station gives goed results. lt will be readily understood, however, that the num ber oif subscribers stations allotted to each auxiliary truniing' station, and the number trunk lines between the .main and auxiliary truriringr st tions, can be varied in accordance 'vith the requirements and 'the conditions oi each particular case.

i the apparatus employed is of an automatic character7 then,A and as a matter oi' further and special improvement, each auX- iliary trunking station will preferably consist of the necessary switching devices inolosed in an air-tight casing or inclosure. With a comparatively limitednuniber of subscribers allotted to each auxiliary trunknnz station,' itis obvious that the said airi tight casing or inclosure may be of vComparatively small dimensions, as the apparatus necessary :tor making the connections between 100 subscribers lines, for example, and trunk lines, may evidently be brought Within a comparatively small compass. Such beine; the case, these air-tight inclosures containingn Vthe switching devices,l and constituting* the auxiliary trunking stations, may be located in any convenient or out ofthe Way place or locality.V Forenaniple, in Figs. 2 and 3, the auxiliary trunlzing station J is located on top of a building. While another auxiliary trunling station K is located in an ordinary `police boX or signaling station; andthe auxiliary trnnking stations L are mounted on the uriner ends of poles. while the auxiliary trunlingr station'i/lr is located in a. man-hole below the surface of the ground. Fig. 4 illustrates more clearly the arrangement of' one of the auxiliary trunking stations on the upper end ci a pole, and in connection with a terminal ring' Z to which the lines can be connected. 0n the other hand` 5 shows the arrangement of an auxiliary trunlring; station Within a 1nanhole. and illustrates the cabling' oi' the trunk lines m. ln '-3 and 7, a round or cylindrical of casing is shown for inclosing the apparatus of the auxiliar.1 trunliing station. Such casing commises a cylindrio shell N, adapted to inclose the switchirncdevices a, and herin tically scaled at its oWcr end by basefplate nl. Any suitable means may be employed for attaching' thc basenlate to the lower edge ot said Shelly i the desiree degree of temperature by means or an incandescent lamp at, or by any other suitable heating arrangement. This, it Will be seen, prevents the apparatus from rusting or corroding, and insures at all times a proper Working of the apparatus. in Fig. 8, the construction is praetically the saine-as in he precedingviews, except that the casing or inclosure is square rather than round.

The single diagram, comprising Figs. 9, 10 and l1, illustrates tivo auxiliary trunk-- infr stations connected with amnain trunking station, and shows three subscribers7 stations connected with each auxiliarytrunking station. At the left of the diagram, in Fig, 9, are the subscribers stations G, l and Q. While at the right ot the diagram, Fig. 1l, are the subscribers R, S and T. As will be observed, the rst mentioned subscribersstations are connected With thethree individual switches U, V and W, which latter are, of course, located at the Aauxiliary trunking station; and it Will also be seen that the three individual or private subscribers lines are connected with the contacts of the three connector-switches X, Y and Z, the latter being also located at the saidl auxiliaryy trunking station and associated With said individual switches. In a similar manner, the subscribers stations at the right ot the diagram are connected With three individual switches U1,-V1 and i' 71. which late ter are located at another trunkingstation; the three individual or private lines leading to these three subscribers stations are also connected With the contacts of the conhector-switches X1, Y1 and Z1. Fig. 10, it will be understood, represents diagrammatically the arrangement of trunk lines and automatic switching apparatus at the main trunlringr station-that is to say, the station through which all connections are made, assuming theI system as a Whole to'involvc the particular arrangement shown. Such being the case, the auxiliary trunkine" station shown in Fig. il is connected withlthe main trunling' station through the medium oi out going` trunk lines O1, and also by incoming trunk lines i, it being observed that t-he trunk t 1e individual switches U, V and `W, While the trunk lines 1 terminate in the relays and step-by-step apparatus -ot the conncoter-switches7 X. Y and Z. ln a similar manner, the auxiliary trunking station shown in Fig. il is connected vWith the main trunking station by means ot outgoing; trunk lines R1, and also by means of incomin ,fr trunk lines S1; it being observe-d that the trunlt lines R1 terminate in the contacts ot' the individual switches U1, V1 and V271, while the trunk lines S1 terminate in the relays and step-by-step apparatus of the connector-sivitches X1, I1 and Z1. 'it is thus inclosed 'same auxiliary trunking station.

lines O1 tcrmiuate in the contacts ot readers? thus evident that the subscribers? lines or individual line connections 0, p, g, and 7', S, t, are normally disconnected from the trunk linesV extending between the auxiliary trunkn ing station and the main trunking station, and that the trunk lines are also normally disconnected from each other. In this Way, each subscriber is connected with the main trunking station by means of normally disconnected line sections. whereof one .is an .individual line connection extending from the subscribers station to the auxiliary trunking station, connection extending between the auxiliary and main trunking stations and adapted to be used in common by all of the different subscribers connected with or allotted to the Itlwill also be seen, however, that each .subscriber may use any one of a certain number of trunk lines for calling out or establishing connection With the main trunling station, and may be called up or-receivc a signal over any one of another set ot trunk lines; the trunk lines over which selecting impulses and signals are transmitted from the auxiliary to the main trunlting station being commonly known as out-going trunk lines, While those over which connecting impulses and signals are received at., and transmitted.

through the auxiliary trunkingstation being commonly known as incoming trunk lines.A As illustrated, the trunk lines O1 are connected `with the relays and step-bystep apparatus or" the Y first selectorswitches O2, 03 and Ot at the main trunk ing station; while the'trunk lines R1 are connected with the relays and step-by-step apparatus of the first selector-switches R2, its and R4 at the main trunlring station. The trunk lines 131 are connected with a. certain level ot contacts of the second selector switches Q1, QL', Qi, Qt, QP and 6; the balance ot the contacts of these second selectorsivitches7 being connected with the trunk lines S1, as' indicated. n addition, the contacts ci the switches O2, 03, 0*, and R2, Rf* and Rt are connected with the relays and. step-bystcp apparatus of the switches Q1, Q2, tf, Q, Q55 and Q6 by means o'flocal trunk lines O5. it the subscribers stations, it is evident that the switching or circuitopening and .closing` devices by which the subscriber is enabled to transmit the necessary impulses over the line circuits may be oi any suitable, known or approved character; but 'in the drawings, and as a simple way of illustrating the operation of an automatic telephone or signaling system, l have shown each sub'scribers equipment as includ,- ing a pair of simple keyvsivitchcs, and also the usual hook-switch. ln the arrangement shown, there is an individual switch for each subsciibes line; but it `vill be readily understoodti A.t the number of connecterand the other a trunlolined tic ico

ille

iliary trunlting station at which are connected with the trunk line i9. This trunk line 19, it will 'be seen, leads from the main trunking station to the any,

which it is connested to the connector-switch X1; and such being the ease, the subscriber at station C can now press the key 10 once, and thereby cause the shaft of switch X1 to move upward one point. After Ithe vertical impulse the key 13 is pressed -once, thereby grounding the rotary line conductor i and permit ting the sitle switch of the connector switch X to pass to second position. The vertical key 10 is then pressed andL the switch shaft olf the switch X1 is rotated one step each time the key l() pressed. This brings the wiper-Contacts 20 into engagement with a pair 'oi' the bank-contacts 2l. The. calling subscriber finally presses the key 13 once, andi the tinal impulse thus sent over the connection allows the side-wipers of the cenneuter-switch to move to third position, thus completing the eoniiection from the calling telephone line through to the eentacts 21, and as these contacts 2l are connected with the local wires 22, which latter connect with the line wires fr, it is evident that the subscribers apparatus at station J is new electrically connected with the sul'- scribers apparatus at station l, provided the called subscriber@ line is not already in use. It the called subscribers line is busy, then the said connector-switch, by reason ot a Well-known provision, will tail to malte the connection, and will instantly release and remain in its busy"-signal7 condition until the calling' subscriber gives up the attempt to get the desired connection; and it will be understood, oi? course, that the calling' subscriber, in banging up 'the receiver after getting; the busy signal, there.- by etl'ects, through any well-known or snit able releasing` arrangen'ient, a restoration of all of the switches which Were employed in establishing, or attempting to establish, connection through to the called subscriberls line. The rurrent 'i'or operating the switch Q1 is' 'furnished by a local battery '23, while the current.l or operating Ithe switch X1 J.f"urnished by the local battery YVhen ronnerliim has thus been automati(zall),f established between the two subscribers7 sintions, the subscriber at station 0 can then employ any suitable signaling arrangement for attracting' the 'attenl ion oit subscriber at station R. Also. it obvious. that atteitlxe automatic establislnnelnt oi electrical con-- neeion between *the two -subscribeis7 stations, the two subscribers Can then converse by means ot any suitable l' )rm oli telephone apparatus. ln the foregoing' marmer, connections can be established between silbseribers wjhose lines terminate at diti'rrent auxiliary'trunking stations; and in all ysuch cases, it is evident that the eonmf-etion between tbe subsrrers elude at lea. i onli lines. new that the s ,lber at tatier e s 1 to communicate with snbscri Aar at station l it being observed that the individual or orivate "ne eonneetions et two sul seribers stations terminate at the same ai, iliary trunling station. n a case et tins kind, the connection between the two subscribers linesI is preferably, as in all other eases, established through the medium ot" inning station-that to say,

tbe main g1 'the subscriber at station O first autonattically connects his line `with one ot the ontgoing trunk linee O1, and then, by suitable manipulation of nis switehing` appar-mns connects the outgoing trunk line with one of the return or incoming trunk lines lm. fitter this, the final step in the establish-A ment of connection between the two subscribers .lines is accomplished by connecting the selected trunk line P1, through the ineclinin of the lconnestor-switch for example, with the local wires 25, which latter are connected with the linibs,.or line wires n leading to the snbscribers station l". T 'mn-tls, t' connection can be made in a ra. rer similar to the one previously descrireu, 'ont with the exeeition that a conne .Jr--sa'itcn at the same viliary trunlm station is employed, ratner than one at a second or distant auxiliary trunking station. That this is true, is nerteetly 7obvious; fen in connecting subscrn'ier s `station O with subseribefs station the Afirst step consists in operating; the individual switch U, and thereby conneeting' the subseribers line 0 with trunk line 9. providing, of course, that tbe latter is idle; lifter this, the switch O2 at the main trunle ing station can be manipulated er operated 'for the purpose of extending the/,connection therefrom to one of the local trunk lines G5. lt the trunk line 16 is idle and available at such time, the switch O2 willestablisli con1 neetion between this trunk line and the eat- ;roing' trunk line SL rthe next rfp consists in manipnlatinfr or operating: the ser-,oral selector-striteh Q1 in snehmanner -as to establish eonnet-tion with one et the incomingor return trnnl-i lines ik" and it the t'rnnlt line 26 is not bu V. itis eyideut that this partit-nlm1 tren line will the one autmnatleally selected by swt( Q1 to do the required work. "Finally, the "*connertor-switch7 X is manipu- AGG ` keys el; suhseiibes s'etion Q in such menner as to @elise ehe sWieh-sheft to move upward, `one peine. l/Vlien this has been done, elle said. shaft is then caused to rotate untili In this either between subsciiloers lines teimi11e.ting at the same oi* different auxiliary trunking stations, are established through the medium of the main trunking station. En every case, tlieiefore, when ewo subscribe's eonveise, elle 'talking ciieui; includes im@ individuel or-pii'vee line connections, en outgoing' and en incoming truuk line,- emi. also n loca-l tiunl line ai', -lhe mein tiunling station. This, ebvioiisly, results in e decided economy with respect to the amount of copper equired-tliet is lgo say, Jshe amount of Wiring or cabling necessay between setiens; emclfthet e meteiial o clecieleclreduction in the ammini of cabling o1* Wiring' neeeeszliy beti'veen stations, even `though it might necessitate e somewhat greater amount of switchboard Lploerzstus L Luid loe theeese if all eik' thesulscibei's;

stations were provided with @Amie indi viduel lines leziclingldirectly to efmein Voicentral stesion, ier im eflvmilege, is evident when it ie teken into eccoiilt *het elle Wiriiig oi cabling between sa'tioiis is,- usually the more ceei'ly of e, sy not only with. respee to inselletien, but also in egeid ie the maintenance of @he system. So ehm Wih :i given number of subscribers, even though the miengemeii "may i'eqiiie e somewhat emeiiiit oli' ewitchboeid apparatus, it is jeefeely clem` thee? by my invention, accomplish e meteml (leef tion in the esseiy lfm' numbei of emouig of cojoL or Wiring me@ giving geel sei-Vice so such e subseiljbes, and thereby provice y signalling e? eleplione system which is, en

the Whole, innen more economical eo erfinlisli maintain in goed w lit is :ilse evidenzi that, in e, syseelm. exilio y" in@ hemiiieiples of QDeAi'eg-iiclee il the lei ehe enit-- ilialy *'mimliing s Wilbe faivelyv sin'mlla el 1 oli couise, thai; elle .matic clieieeer. be seen ihel, he ine er oie inelosui'e ceivhe healed im Y lenient mamme?, `but prei'e el) un incendies lenig, oi: some heet-generating junetiu'e il: Quay can he obtain side of Howl nmie mieli ehziec'ezg il; feature, and

engages the benlecontecte Way, es explained, all eohiections accomplished in i one silbcibers line 'with autematie exchange known decimal sys' will be seen that, ley my imp ment, the' leet two cleeieiiels numb-ei celled tiunling stelion i me f mote from l1'che mein o3? ceeffe which may he eihei' the seme e auxiliary timiing il ioi which ehe Cell oiigieeeel..v proved exchange eysem i. tei-ially iecluee the cost siiiction necesse. subscribers, geziei ecenomy results of e system of this eherect steliecl, in liis conneewbieii7 viel; limit :myselll to ely periculei" A tiu'nl lines, noi* ve mi" 1Q of mein or auxiliary Furtheimoi'e, l (le not lili,klu vertici/ller uuml;

s to :i 1y pe ltifmlel hoe cl eppeetu j o switching (levi Lions foiiiienipula tomaitie sivilching Je plof/ed nii the main or s'atifme. Again, I (lo any paitieul i' nimh Whi fh e subscriber L (MWA.

Je einY evi-:lense th maliens l ineens? ing the second decimal or digit of the called number; or at least the terms first and second selectors are employed to designate, switches which receive and are operated by an impulse or impulses representing one or more digits of the called number. Consequently, the said individual switches may be the same in number as the number of subscribers, while the first and second selectors and connectors, and any other similar switches, can all be installed on a percentage basis. In this way, the number of' irst selectors is materially reduced, it having been the practice, prior 'to my invention,rto employ as many so-called irst '.selectors-that is, switches operated by the first impulse or impulses sent over the line in calling the number of the desired subscriberfas there were subscribers lines terminating at the exchange or central station. As stated, however, the employment of individual switches, which have no other function than to receive the impulse or impulses sent over the line preliminary to calling the desired number, permits the number of' first selectors to be reduced to a percentage basis-that is to say, to ten per cent., for example, of the total number of subscribers.v Each individual switch when operated by its allotted subscriber, automatically picks out an idle or non-busy irst selector In this way, the first selector is connected with the calling subscribers line, and is in readiness for use, by the time the calling subscriber is ready to begin calling the number of the desired subscriber.

It is obvious that any suitable arrangement can be employed at the subscribers stations, and in the different automatic switches throughout the exchange, for releasing or restoring all of the different switches after the conversation is terminated. For example, it is the practice in certain automatic systems now in use, and of the character herein described and illustrated, to so arrange the apparatus that the act of replacing the receiver at the subscribers station serves to momentarily ground the subscribers line, and thereby bring about the operation of releasing 'circuits and devices atthe different switches, resulting in the restoration of the different step-by-step switching mechanisms employed by the calling subscriber in seeuring connectionl with the called subscribers line. and circuit arrangement shown and described inay include a releasing arrangement of this or any other suitable character.

Also, the means whereby any trunk-line, or subscribers line, while in use, is made busy, so to speak, so that a third subscriber can not establish connection with either one It is obvious that the constructionV of the two subscribers who are already conversing, nor with any vof the trunk-lines which the two subscribers are using, may be of' any suitable, known or approved character. ln a similar way, the mechanical and electrical arrangements whereby the individual switches, and also the first and second selectors, are each adapted to rotate automatically until an idle trunk-line is selected, may be ofy the usual or any other suitable or desired character. And for like reasons, the construction and arrangement whereby the different connectors are each adapted to rotate only in accordance with the impulses which the calling subscriber sends over the line-circuit, corresponding to the last two digits of the called number, may be of anyvknown or suitable character.

As previously stated, the construction of the different automatic nvitches may be of any suitable, known or approved character. For example, each of the said individual-switches7 may be of the general construction and character shown in Fig. 1Q. ln this figura which is an enlargement of the individual-switeh U, for example, the circuit arrangement or electrical construction is quite fully illust-rated, while only so much of the mechanical construction is shown as is necessary to' understand the operation, and to identify the general type of switch. In this figure, the step-by-step mechanism and other mechanica] parts` to` get-her` with the Operating magnets, are shown in perspective, while the relays are shown in side elevation; and it will be understood that the framework for supporting the various elements may be oi anyY suitable or desired character, but is omitted for convenience of illustration, The construction includes the usual switch-shaft u provided at its lower end portion with the privatewiperj` u1 and with the Vertical and rotary wipers u? and H3, all insulated from each other and from the shaft. The wiper u1 is adapted to engage any one of thi` ten cont-acts in the private-bank" n4, while the` said vertical and rotary7 linewipers"' are adapted tol engage an)v one of the ten pairs of contacts in the line-bank its. /The vertical and rotary linetrunk-condnctors u. and u? lead to a first selecton it being understood that each pair of contacts included in thc line-bank are connected with a trunk-line leading to a first selectoiz vatebank 11,4 is connected, as` for byrineans of a. private-multiple u8, with a corresponding private-baiik-contact` in each or' the other indiridual-switches" helonging to the subscribersin this particular grouphthat is to say, all cprivate-luukcontacts allotted to a certain trunk-line leading from this Agroup are multiplediogether; anti it will also be understood that example Each contact in the pri 

